The present invention relates to a seal for an antifriction bearing, and more particularly to an elastic layer between a sealing part of the seal and the adjacent bearing ring.
Seals are known in which at least one sealing part comprises an L-shaped part fabricated of sheet metal and provided with an elastic lip. These metal seals were previously pressed directly into the receiving parts, e.g. into the bearing rings. The sheet metal parts are produced by plastic deformation. They are not very precise or of sufficiently flexible material. As a result, when they are in the seated position in the receiving part, e.g. the bearing ring, gaps are present which substantially reduce the sealing action.
This problem has been eliminated by applying an elastic layer over the entire width, or at least over a part of the width, of the sealing part in the external region of the sealing part which engages the bearing ring. This elastic layer compensates for inaccuracies and avoids leakage points in the region of the seat of the sealing part. These embodiments, however, have the disadvantage that in one type, in which an elastic layer of only small thickness is applied, the layer is completely stripped-off upon the pushing on of the sealing part onto the seat.
One solution is to apply a thicker elastic layer by vulcanizing it on. This is not disadvantageous for manufacturing if, for instance, the sealing lip is vulcanized onto the L-shaped sheet metal parts. However, the situation is unfavorable in the case of sealing parts which consist of sheet metal parts alone. They have to be further provided with a layer vulcanized in place, which is quite expensive.